Foaming agents



Patented Aug. 4, 193a murscruan or ws-rrma sun some scams Arnon O. Snoddy and Wilfred 8.

Cincin- Martin. nati, Ohio, assignors to The Procter dz Gamble Oompany, Cincinnati, Ohio. a corporation of Ohio *No Drawing. Appli Serial No. 646,708. rose cation December 10, 1933,

Renewed January 17,

ricmm. (c1. sec-sale) This invention relates to a process for producing wetting and foaming agentsconsisting essentially of metallic salts or the sulfuric esters of alcohols by the direct union of alcohols with the 5 reaction products of sulfur trioxide on metallic chlorides. Its object is to provide a practical. convenient, and economical process for the production 01 such products. Many oi the metallic salts of alkyl sulfuric esters have valuable wet-- l ting, emulsifying, and detergent properties, es-

pecially those containing from 12 to 22 carbon atoms, such as may be obtained from the alcohols made, from oils and fats by known means.

The usual procedure in the past for producing l the above mentioned compounds has been to first produce the acid sulfuric ester 01' the alcohol, which in this case was usually an aliphatic alcohol, and then to neutralize same by treatment with oxides, mrdroxides, or carbonates of the go metals to form the desired salts. The sulfuric esters have usually been previously formed in such cases by the reaction of. aliphatic alcohols with concentrated sulfuric acid in excess or by the reaction of aliphatic alcohols with chlor-sul- 25 tonic acid. In the latter case, it is not necessary to use such a large excess of the acid, and in practice it is round that as much as 90% or 95% of the alcoholused can be converted into the sulfuric ester. 30 our improvement arises from the discovery that good wetting agentsconsisting of metallic salts of sulfuric esters of higher alcohols can be made directly by the reaction between such alcohols and the product obtained by action of sulfur 35 trioxide on alkali chlOl'ldB Oi. similar chlorides.

The treatment of sodium chloride or other chloride with sulfur trioxide is. not a part of the present invention.

We find that when a higher alcohol is mixed 40 ,with the reaction products of sulfur trioxide on metallic chlorides. a; chemical reaction takes place with the evolution of hydrochloric acid gas,

and there is formed a metallic salt of the sulfuric I ester-of the alcohol. Various salts may be used, 45 especially those of the alkali metals, the alkali earth metals or ammonium, as well as various .other metals. It is possible in this reaction to.

have thelarger part of the alcohol converted into the sulfuric ester without using a large ex- 50 cess of the said reaction products oi sulfur triox ably to grind it in a suitable apparatus, such as a ball mill, during the progress oi the reaction. in this way, the reacting material may be kept in intimate contact. Another method for facilitating the progress of the reaction is to use an in- 5 ert liquid medium in which the materials can be dissolved or suspended and thereby kept in intimate contact. Carbon tetrachloride and various other chlorinated hydrocarbons, such as dichlorethane, may be used for this purpose. )0

It is obvious that the reaction may be carried out either with a single alcohol or a mixture of alcohols. Mixtures of the higher alcohols suitable for this purpose may be obtained by known procedures from the commercial oils and fats, is which will produce alcohols having carbon contents varying usually between 12 and 22 carbon atoms.

Hereinafter in'these specifications, for the purpose of fully disclosing an exemplary embodiment of our invention, we shall describe a process of producing compounds from higher aliphatic alcohols', it being understood that our invention is not restricted to aliphatic alcohols.

At the end of the reaction referred to. the metal 25 sulfuric ester may be purified from the other materials, such as unconverted raw materials and small amounts of by-products in various known ways such as by dissolving the mass in a suitable solvent and allowing it to crystallize either by cooling the solution or by the removal of a portion of the solvent by evaporation. We have found that a suitable method is to wash the crude product with a solvent in which the impurities are more soluble than is the metallic salt of the sulfuric ester. The purified material, when dissolved in water, shows remarkable wetting, sudsing. emulsifying and detergent properties.

In carrying out this invention in its exemplary form. we proceed as follows:

One hundred parts of an aliphatic alcohol, such as lauryl alcohol, may be used together with 84 parts of finely ground reaction products of sulfuric anhydride on potassium chloride. The lauryl alcohol is placed in any suitable mixing or grinding device, such as a ball mill constructed of acid-prooi'material, such as porcelain, for example, and suitably arranged to allow evolution of the hydrochloric acid gas formed in the reac-- tion and also immersed in a water bath or provided with other arrangement for cooling. The reacting materials must be substantially anhydrous andcare must be taken to avoid contact with moisture. The potassium reaction products above mentioned are added to the alcohol in small portions at a time and mixed, or ground in the mill, to effect the desired reaction while the temperature is controlled so that the reacting mixture does notreach too high a temperature,- preferably not higher than about 30 C. Excessively high temperatures form undesired products. The reaction is allowed to continue until no further action takes place, at which time it is found that about 90 .to 95% of the alcohol is used up. The mass is then discharged from the mixer or mill and should preferably then be neutralized, and purified if necessary, as follows:

If the material is to be used for purposes not requiring a high degree of purity, it may be mixed with about one-third to one-half its weight of water containing a, small excess of potassium hydroxide or carbonate over that required for complete neutralization of the free acid remaining in the mix. This forms a pasty mass which shows the characteristic valuable detergent, wetting and emulsifying properties when mixed with water, and is especially useful for these purposes in hard water or in sea water. If a dry product is desired instead of the paste, it may be dried by any'of the ordinary procedures, such as are used for drying soap, for example, or after suitable dilution with additional water, it may be dried by the spray drying procedure.

If a purer product than the above is required, the mixture may be discharged into a suitable solvent, such as ethyl alcohol, containing a slight excess of potassium hydroxide over that necessary to neutralize the acidity of the discharged mixture. Suflicient alcohol should be used in this case to dissolve the potassium lauryl sulfate, and the hot alcoholic solution is then filtered from insoluble impurities and cooled to allow the pure lauryl potassium sulfate to crystallize out. After separating the crystallized material, as by any suitable means, further amounts of the product may be obtained by evaporating ofl some of the alcohol and again allowing the solution to cool and crystallize.

Another procedure which may be used for purifying the product is to discharge the mass from the ball mill into ethyl or other suitable alcohol containing potassium hydroxide in slight excess over that required to neutralize the free acid, and then filter and evaporate off the solvent alcohol, preferably at a low temperature to avoid injury to the product, and also preferably using means. Alcohols obtained from cocoanut oil and tallow, for example, have been found to produce very satisfactory products by our procedure.

Instead of using the potassium salt of the said reaction products with sulfur trioxide, it is also possible to use V the sodium salt, the ammonium salt, and salts of other metals; those of the alkali group and the alkali earth group are especially suitable. When other bases than potassium are used, it is, of course, understood that the same base will ordinarily be used in the subsequent neutralization. It is also understood that the quantities above mentioned for use with lauryl alcohol and potassium chlor-sulfonate will be modified when other materials are used in order to have the proper relation of their chemical reacting weights. Both saturated and unsaturated alcohols, may be used in this reaction.

Instead of carrying out the reaction as above described, thealcohols may be mixed with from one to five times their weight of carbon tetrachloride or dichlorethane, etc. in an acid-proof mixing vessel. The necessary weight of the previously described reaction products is then stirred into the mixture gradually while keeping the temperature of the mass preferably below approximately 30" C. and allowing the hydrochloric acid gas which is formed in the reaction to escape. When the reaction is completed, the mixture is transferred to a distilling apparatus where the inert liquid medium is distilled ofl, using preferably a low temperature and vacuum. The product may then be neutralized and purified by any of the procedures above mentioned. The product is-the same as that obtained by using the first described procedure.

Having thus described our invention, what we claim as new and desire to secure by LettersPatent is:

1. The process of making a wetting and sudsing agent which comprises causing a higher al- 001101 to react with the reaction product of sulfur trioxide on a metal chloride.

2. The process of making a material whose water solution has good wetting, sudsing, emulsifying and detergent properties, which consists in causing a mixture of higher aliphatic alcohols to react with the reaction products of sulfur trioxide on a metal chloride.

3. The process of making a material whose water solution has good wetting, sudsing, emulsifying and detergent properties, which comprises causing one or more higher aliphatic alcohols to react with the reaction product of sulfur trioxide on a metal chloride.

4. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises reacting a higher aliphatic alcohol with the reaction product of sulfur trioxide on a metal chloride, neutralizing the product and purifying the same by washing out impurities with a suitable solvent.

5. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises reacting the alcohols obtained by hydrogenation of coconut oil with the reaction product of sulfur trioxide on sodium chloride, in the presence of an inert liquid medium.

6. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises reacting the alcohols derived from coconut oil with the reaction product of sulfur trioxide on sodium chloride, in the presence of an inert liquid medium.

'7. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises reacting the alcohols obtained by hydrogenation of coconut oil with the reaction product of sulfur trioxide on sodium chloride, neutralizing the product and purifyingthe same by washing out the impurities with a suitable solvent.

8. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises reacting the alcohols derived from coconut oil with the reaction product of sulfur trioxide on sodium chloride, neutralizing the product and with a suitable solvent.

the product and purifying same by dissolving in a suitable solvent, filtering the solution and recrystallizing said agent from said suitable solvent.

11. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises causing alcohols characterized by the presence or molecules having from twelve to twenty-two carbon atoms each, to react with the reaction product of sulfur trioxide on a metal 10 chloride.

ARNON O. SNODDY. WILFRED S. MARTIN. 

